docs: def get_more(collection_name, num_to_return, cursor_id):
      """Get a **getMore** message.
      """
      data = __ZERO
      data += bson._make_c_string(collection_name)
      data += struct.pack("<i", num_to_return)
      data += struct.pack("<q", cursor_id)
      return __pack_message(2005, data)